已阅读5页,还剩9页未读, 继续免费阅读
版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
英文原文Minehoistingindeepshaftsinthe1sthalfof21stCenturyAlfredCarbogno1Keywords:deepshaft,minehosting,Blairwinder,ropesafetyfactor,drumsizing,skipfactorIntroductionThemineraldepositsareexploitedondeeperanddeeperlevels.Inconnectionwiththis,definitionslike“deeplevel”and“deepshaft”becamemoreandmorepopular.Thesedefinitionsconcernthedepthwherespecialrulesregardinganexcavationdriving,exploitation,rockpressurecontrol,liningconstruction,ventilation,undergroundandverticaltransport,workorganizationandeconomicsapply.Ithaspointedoutthatthe“deeplevel”isaveryrelativedefinitionandshouldbeusedonlywithareferencetoparticularhydro-geological,miningandtechnicalconditionsinamineorcoal-field.Itshouldbealsostrictlydefinedwhatareaof“deeplevel”or“deepshaft”definitionsareconsidered.Itcanbeforexample:-mininggeo-engineering,-technologyofexcavationdriving,-ventilation(temperature).Itisobviousthatthe“deeplevel”definedfromonepointofview,notnecessarilymeansa“deeplevel”inanotherarea.Accordingto5asadeepminewecantreateachmineif:-thedepthishigherthan2300mor-mineraldeposittemperatureishigherthan38C.ItiswellknownthatthemostofdeepminesareinSouthAfrica.Usually,theyaregoldordiamondsmines.Economicdepositsofgold-bearingoreareknowntoexistatdepthsupto5000minanumberofSouthAfricaregions.However,duetothedepthandstructureofthereefinsomeareas,previousmethodsofreachingdeeperreefsusingsub-verticalshaftsystemswouldnotbeeconomicallyviable.Thus,thelocalminingindustryisactivelyinvestigatingnewtechniquesforasingle-liftshaftupto3500mdeepinthenearfutureandprobablyaround5000mafterwards.Whencomparedwiththemaximumlengthofwindcurrentlyinoperationof2500m,itisapparentthatsomesignificantinnovationswillberequired.Themostimportantmatterinthedeepmineistheverticaltransportandtheminehoistingusedintheshaft.Fromtheliterature1-12resultsthatB.M.R.(BlairMulti-Rope)hoistispreferredtobeusedindeepminesinSouthAfrica.Fromtheeconomicpointofview,themostimportantfactorsare:-constructionandparametersofwindingropes(safetyfactor,mainly),-minehoistingdrumscapacity,Thisarticleofinformativecharacterpresentsshortlyabove-mentionedproblemsbasedontheliteraturedata1-12.Especially,thepaperwrittenbyM.E.Greenwayisveryinteresting3.Fromtwotransportsystemsusedinthedeepshaft,sub-verticalandthesingle-liftshaftsystems,thesecondoneiscurrentlypreferred.(Fig.1.)6HoistingInstallationThefrictionhoist(upto2100m),singledrumandthedoubledrum(classicandBlairtypedoubledrum)hoistareusedindeepshaftsinSouthAfrica.DrumwindersDrumwindersaremostwidelyusedinSouthAfricaandprobablyintheworld.Threetypesofwindersfallintothiscategory-Singledrumwinders,-Doubledrumwinders,-Blairmulti-ropewinders(BMR).DoubledrumwindersTwodrumsareusedonasingleshaft,withtheropescoiledinoppositedirectionswiththeconveyancesbalancingeachother.OneorbothdrumsareclutchedtotheshaftenablingtherelativeshaftpositionoftheconveyancestobechangedandpermittingthebalancedhoistingfrommultiplelevelsTheBlairMulti-RopeSystem(BMR)In1957RobertBlairintroducedasystemwherebytheadvantageofthedrumwindercouldbeextendedtotwoormoreropes.Thetwo-ropesystemdevelopedincorporatedatwo-compartmentdrumwitharopepercompartmentandtworopesattachedtoasingleconveyance.Healsodevelopedaropetension-compensatingpulleytobeattachedtotheconveyance.TheDepartmentofMinesallowedthestatutoryfactorofsafetyforhoistingmineralstobe4,275insteadof4,5providedthecapacityfactorineitherropedidnotfallbelowthestatutoryfactorof9.Thisnecessitatedtheuseofsomeformofcompensationtoensureanequitabledistributionofloadbetweenthetworopes.Becausethepulleycompensationislimited,Blairalsodevelopedadevicetodetectthemiscallingonthedrum,asthiscouldcausetheropestomoveatdifferentspeedsandsoaffecttheirloadsharingcapability.Fig.2showsthedepthpayloadcharacteristicsofdoubledrum,BMRandKoepewinders.TheB.M.R.hoistisusedalmostexclusivelyinSouthAfrica,probablybecausetheywereinventedthere,particularlyforthedeepshaftuse.ThereisoneinstallationinEngland.Becauseofthishoistsphysicalcharacteristics,andSouthAfricanminingrulesfavouringitinonerespect,theyareusedmostlyforthedeepshaftmineralhoisting.Thedrumdiametersaresmallerthanthatofanequivalentconventionalhoist,sooneadvantageisthattheyaremoreeasilytakenundergroundforsub-shaftinstallations.ABlairhoistisessentiallyaconventionalhoistwithwiderdrums,eachdrumhavingacentreflangethatenablesittocoiltworopesattachedtoaskipviatwoheadsheaves.Theskipconnectionhasabalancewheel,similartoalargemulti-grooveV-beltsheave,toallowmoderateropelengthchangesduringwinding.Thesheavescanraiseorlowertoequalizeropetensions.TheBlairhoistsphysicaladvantageisthatthedrumdiametercanbesmallerthanusualand,withtworopestohandletheload,eachropecanbemuchsmaller.Thegovernmentminingregulationspermita5%lowersafetyfactoratthesheaveformineralhoistingwithBlairhoists.Thiscameaboutfromademonstrationbythe%permitstheBlairhoiststogoalittledeeperthantheotherdo.Ontheotherhand,theminingregulationsrequireadetachinghookabovethecageformanhoisting.Thebalancewheeldoesnotsuitdetachinghooks,soarope-cuttingdevicewasinventedtocuttheropesoffforasevereoverwind.ThiswastestedsuccessfullybuttheBlairisnotusedformanwindingonaregularbasis.TheB.M.R.hoisthasbeenbuiltinthreegeneralstylessimilartoconventionalhoists.Thethreestylesare(Fig.3and4):ThegearlessB.M.R.hoistatEastDreifonteinlookssimilartoanin-linehoistexceptthatthedrumsarejoinedmechanicallyandtheyarealittleoutoflinewitheachother.Thisisbecauseeachdrumdirectlyfacesitsownsheavesforthebestfleetangle.Thetwohoistmotorsarefedviathyristorrectifier/inverterunitsfromacommon6.6-KVbusbar.Themotorsarethuscoupledelectricallysothattheskipsintheshaftruninbalance,similartoaconventionaldouble-drumhoist.EachmotoralternatesitsactionasaDCgeneratororDCmotor,eitherfeedinginortakingoutenergyfromthesystem.ThegearlessBlaircanberecognizedbytheoffsetdrumsandthefourbrakeunits.Asecondbrakeisalwaysarequirement,each
温馨提示
- 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
- 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
- 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
- 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。
最新文档
- 2024年岗位知识竞赛-税务系统岗位练兵知识竞赛笔试参考题库含答案
- 2024年安全知识安全生产知识竞赛-安全生产风险防控指南笔试参考题库含答案
- 质量员之市政质量基础知识全真模拟考试试卷A卷含答案
- 智慧景区建设方案
- 2024年大学试题(管理类)-技术与质量管理笔试参考题库含答案
- 2024年大学试题(社会学)-礼仪学笔试参考题库含答案
- 2024年大学试题(汽车专业)-汽车车身结构与设计笔试参考题库含答案
- 2024年大学试题(文学)-汉语史笔试参考题库含答案
- 2024年大学试题(教育学)-成人教育学笔试参考题库含答案
- 2024年新国货行业现状及发展趋势研究
- 儿童心肺复苏指南培训
- 房产证模板表格
- 部编版二年级道德与法治下册全册课件
- 小箱梁桥尺寸标准是多少?构造尺寸如何拟定
- 石化生产指挥信息系统项目可行性研究报告课件
- ad830培训资料详细
- 《小马过河》完美课件(共17张)
- 小学《垃圾的危害》课件
- 复调音乐课件
- 2023学年广州市广大附中中考联考英语试题含答案解析
- 乳酸杆菌培养基配方
评论
0/150
提交评论